Circuit interrupting means



Dec- 17, 1957 s. 1. LINDELL 2,816,983

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Dec. 17, 1957 s. l. LINDELL CIRCUIT INTERRUPTING MEANS 4 Sheets-Sheet 3 Original Filed June 19, 1955 v fi yard Z lcizdell S. l. LINDELL CIRCUIT INTERRUPTING MEANS Dec. 17, 195 7 4 Sheets-Sheet 4 Original Filed June 19, 1955 Jm -a-aasas Hiii-.555

United States Patent CIRCUIT INTERRUPTING MEANS Sigurd I. Lindell, Chicago, 111., assiguor to S & C Electric Company, Chicago, 11]., a corporation of Delaware Application February 12, 1954, Serial No. 409,809, which is a division of application Serial No. 362,891, dune 19, 1953, now Patent No. 2,671,142, dated March 2, 1954. Divided and this application May 22, 1957, Serial No. 660,967

7 Claims. (Cl. 200114) This invention relates, generally, to electric circuit interrupters, and it has particular relation to the application of circuit interrupter for disconnecting under a load a conventional circuit isolating or switching device, such as a disconnecting fuse, a disconnecting switch or the like without drawing an arc between the energized parts thereof which are separated or disconnected as an incident to the circuit isolating operation as usually attempted to be effected by a lineman by means of a switch stick and to necessary modifications of circuit isolating and interrupting devices to adapt them for use with such circuit interrupters. This application is a division of application Serial No. 409,800, filed February 12, 1954, which is a division of application Serial No. 362,891 now Patent No. 2,671,142 issued March 2, 1954.

It is sometimes necessary to deenergize a high voltage electric power circuit carrying load current by swinging a pivotally mounted fuse to open circuit position without rupturing its fusible elements. Or it may be necessary to accomplish this by opening the blade of a conventional disconnecting switch under these conditions, the switch blade having no particular means for interrupting the arc incident to its being opened. When these operations are performed, an arc is drawn between the energized parts last in engagement since, under the assumed conditions, load current or line current is flowing. The are is likely to cause severe burning of these parts or it may jump to ground or to an adjacent circuit and create a fault causing damage. At any event it is likely that operation of one or more circuit interrupters closer to the power source will be required in order to'clear the fault thus caused.

Accordingly, among the objects of this invention are: To provide for simply, efliciently and economically opening an energized current carrying high voltage electric power circuit by swinging a fuse or disconnecting switch blade to open position without rupturing the fusible element of the former and without causing the are between the energized parts of the fuse or the switch last to separate; to shunt the separable parts of the fuse or switch by an auxiliary circuit interrupter that is arranged to draw and extinguish the are within itself after the parts of the fuse or disconnecting switch or other circuit breaking device have been separated; to extinguish the are quickly and positively within the auxiliary circuit interrupter without external arcing; and to provide for mounting the auxiliary circuit interrupter on an energized part of the fuse or switch so that it can be readily attached thereto and detached therefrom as manipulated by a live line stick.

Other objects of this invention will, in part, be obvious and in part appear hereinafter.

This invention is disclosed in the embodiment thereof and method shown in the accompanying drawings, and it comprises the features of construction, combination of elements, arrangement of parts and method of operation which will be exemplified in the construction and method 2,816,983 Patented Dec. 17, 1957 hereinafter set forth and the scope of the application of which will be indicated in the appended claims.

' For a more complete understanding of the nature and scope of this invention, reference may be had to the following detailed description taken together with the accompanying drawings, in which:

Figure 1 is a view in side elevation of a conventional form of dropout fuse construction such as that described in more detail in Ramsey United States Patent No. 2,247,700, issued July 1, 1941, certain parts of the terminal assembly at the upper end being broken away in order to illustrate the details of construction;

Figure 2 is a top plan view of the circuit isolating device or dropout fuse shown in Figure 1;

Figure 3 is a view, in side elevation, of the dropout fuse construction shown in Figure 1, at a reduced scale, and illustrating the application of the auxiliary circuit interrupter of the present invention thereto for eifecting the opening of the fuse or disconnecting device without causing arcing between the parts thereof last to separate;

Figures 4 and 5 are views, similar to Figure 3, showing successive stages in the opening of the fuse or disconnecting device by means of the auxiliary circuit interrupter;

Figure 6 is a view at an enlarged scale, certain parts being broken away, illustrating the general construction and arrangement of the auxiliary circuit interrupter, the view being taken looking from right to left with respect to the auxiliary circuit interrupter as illustrated in Figures 3, 4, and 5;

Figure 7 is a longitudinal sectional view of the auxiliary circuit interrupter, the separable contacts being shown in the fully closed position;

Figure 8 is a view, similar to Figure 7, but illustrating the relative location of the parts after the separable parts of the fuse have been separated and after the movable auxiliary interrupter contact has been operated only a slight distance from its cooperating relatively fixed contact;

Figure 9 is a view, similar to Figures 7 and 8, but illustrating the relative positions of the parts of the auxiliary circuit interrupter when its separable contacts are in the full open position; and

Figure 10 is a view, in side elevation, of a modified form of contact arm for gripping the pull ring of the fuse, disconnecting switch or the like.

Referring now particularly to Figure 1 of the drawings, it will be observed that the reference character in designates, generally, a circuit isolating device or switching device which, in this instance, is a dropout fuse construction such as described in more detail in Ramsey Patent No. 2,247,700 issued July 1, 1941, and referred to above. However, it will be understood that the present invention can be used in conjunction with other circuit isolating devices, such as disconnecting switches in which a switch blade is swung from the closed to the open position for the purpose of introducing an air gap into the circu1t.

The particular dropout fuse construction 10 includes an insulator 11 which carries terminal assemblies 12 and 3 at its ends for connection to line conductors as will be understood readily. Pivotally mounted at 14 on the lower terminal assembly 13 is a fuse tube that is indicated, generally, at 15. The fuse tube 15 contains a fusible element which is arranged to be ruptured on flow therethrough of excess current and mechanism is provided for automatically unlatching the fuse tube 15 from the upper terminal assembly 12 so that it can fall to the open circuit position. When this occurs, the circuit is interru ted within the fuse tube 15 and the arc incident thereto is extinguished. Ordinarily under fault conditions, the circuit will be interrupted within the fuse tube 15 before it swings out of contact with the upper line terminal assembly 12.

ICC

The present invention has to do particularly with the provision of mechanism for effecting the opening of the circuit under load by bodily moving the fuse tube 15 to the open circuit position while it still contains a fuse link that has not been ruptured by overcurrent. Provision is made for accomplishing this while load current is flowing through the fuse tube 15 in such manner that no arc is drawn between it and the upper terminal assembly 12 during the circuit opening operation.

At its upper end the fuse tube 15 has a fuse tube terminal assembly indicated, generally, at 16. This assembly includes a sleeve 17 that is slidable upwardly relative to the fuse tube 15 and formed integrally with the sleeve 17 is a hook 18 which is held in latching engagement with a roller 19 carried by the upper terminal assembly 12. When the fuse link within the fuse tube is ruptured, the sleeve 17 is moved upwardly to such position that the hook 18 no longer engages the roller This same operation can be accomplished by means of an open ating arm 2i) which is pivoted at 21 on the fuse tube terminal assembly 16. At its outer end the operating arm 21? has a pull ring 22 which is arranged to be engaged by the prong of a switch stick or the contact arm of the auxiliary circuit interrupter to be described hereinafter. When the pull ring 22 is swung in a counterclockwise direction about the pivot 21, the sleeve 17 is moved upwardly so that the hook 18 clears the roller 19. The fuse tube 15 then can be swung or allowed to fall to the open circuit position.

When the fuse tube 15- is operated in the manner just described by the prong of a switch stick engaging the pull ring 22, an arc will be drawn between the portions of the terminal assembly 12 and fuse tube terminal assembly 16 last to separate. As indicated above, such an arc may damage severely these terminal assemblies or it may cause a fault on the circuit. In accordance with the present invention, the fuse tube 15 can be unlatched from the upper terminal assembly 12 and swung to the open position without drawing an arc between the terminal assemblies 12 and 16. The manner in which this is accomplished, generally, is by providing a shunt circuit between the terminal assemblies 12 and 16, unlatching the fuse tube terminal assembly 16 from the upper terminal assembly 12, swinging the fuse tube 15 to such a position that an air gap is provided between the terminal assemblies 12 and 16 and then interrupting the circuit by separating contacts within the auxiliary circuit interrupter under such conditions that the arc is confined and extinguished quickly. The only modification required in the construction of the circuit breaker for accommodating the auxiliary circuit interrupter comprises providing the sleet hood 23, formng a part of the terminal assembly 12, with a transversely extending conducting arm 24-. As will appear hereinafter, this provides a fixed support for the auxiliary circuit interrupter while it is being employed for swinging the fuse tube to open position without arcing between the terminal assemblies 12 and 16.

For the purpose of operating the dropout fuse 1th to the open position without arcing, a generally tubular auxiliary circuit interrupter, shown generally at 25, is provided. Its application to the dropout fuse 1b is illustrated in Figure 3 and the details of construction are shown more clearly in Figure 7 to which reference now will be had.

It will be noted that the auxiliary circuit interrupter 25 has a relatively fixed conducting member 26 at its upper end to which a metallic cap 27 is secured by cap screws 28. A conducting eye member 29 is pivoted or swiveled at 30 on the metallic cap 27, and it comprises a pair of resilient contact extensions 31 which are bowed outwardly as indicated at 32 for facilitating entry of the transversely extending conducting arm 24 carried by the sleet hood 23. In order to provide good contact engagement with the conducting arm 24, the upper portion 33 of the extensions 31 are positioned in side by side relationship and biased toward each other by the inherent resiliency of the contact extensions 31. Because of this construction, they grip the conducting arm 24 tightly therebetween. The upper ends 34 of the contact extensions 31 are turned outwardly, as shown, and interfit with a keeper 35 which not only limits the movement apart of the upper portions 33 but also serves as a stop to me vent relative movement between the eye member 29 and the conducting arm 24 when a downward pull is applied to the auxiliary circuit interrupter 25 in a manner to be escribed.

Depending from the relatively fixed conducting member 26 is an insulating sleeve 38. It may be formed of a suitable phenolic condensation product. Intermediate the cnds of the insulating sleeve 38 is a ringlike contact 39 that is electrically and mechanically connected by a conducting sleeve 40 to the conducting member 26 at the upper end of the insulating sleeve 38. It will be observed that both the insulating sleeve 38 and the conducting sleeve 40 are threaded into the underside of the conducting member 26. Cooperating with the ringlike contact 39 is a rodlike contact 41 having a bifurcated resilient contact portion 42 at its upper end for engaging the ringlike contact 39. Below the ringlike contact 39 is a liner 43 of insulating material which is capable of evolving an arc extinguishing medium when subjected to the heat of the arc. The liner 43 may be formed of a stack of fibre rings or other suitable material for this purpose. With a view to restricting the area within which the arc can ply between the contacts 39 and 41 when they are separated, an insulating trailer 44 is connected to the rodlilre contact 41 and is arranged to be moved conjointly therewith into the bore formed by the liner 43 of insulating material. The trailer 44 is also formed of a material which evolves an arc extinguishing medium. For example, it may be formed of methyl methacrylate resin. Ports 45 are provided in the conducting member 26 and extend radially therefrom for venting the interior of the auxiliary circuit interrupter 25 so that destructive pressure will not be built up within it during the circuit interrupting operation. The rodlike contact 41 is provided with a shoulder 46 spaced from its upper end for cooperating with a tubular stop member 47 that is carried by a metallic fitting 48 threaded into the lower end of the insulating sleeve 38. The stop member 47 has an inturned lower end portion 49 which cooperates with the shoulder 46, as shown more clearly in Figure 9 of the drawings, to limit the downward movement of the rodlike contact 41.

Provision is made for maintaining the rodlike contact (-1 in engagement with the ringlike contact 39 as shown in Figure 7. For this purpose the rodlilae contact 41 is provided with a shoulder 52 near its lower end which is arranged to cooperate with resilient fingers that are carried by and depend from the metallic fitting 43. A garter spring 54 surrounds the fingers 53 and urges their lower inturned ends into mechanical contact engagement with the underside of the shoulder 52. This construction serves to hold the rodlike contact 41 in the position where it is in engagement with the ringlike contact 39. However, when sufiicient force is applied to the rodlike contact 41, the shoulder 52 moves downwardly to such position that the resilient fingers 53 are moved out of engagement therewith, as shown in Figure 8, whereupon the rodlike contact 41 can move quickly toward the open circuit position.

It is important to know whether the contacts 39 and 41 are in engagement or out of engagement. For this purpose an indicator 55 is employed. As shown in Figure 7, it constitutes an extension of the lower end of the rodlike contact 41. Its indicating function will be described in more detail hereinafter.

A flanged metallic fitting 56 is secured by a transverse pin 57 to the rodlike contact 41 at a position just below the shoulder 52. This flanged metallic fitting 56 cooperates with a spacer sleeve 58, depending from the metallic fitting 48, for limiting the upward movement of the rodlike contact 41 and positioning its upper end contact portion properly with respect to the ringlike contact 39.

Surrounding and telescoped with the insulating sleeve 38 and freely axially rotatable with respect thereto is a metallic sleeve 59. At its upper end the metallic sleeve 59 has an end ring 60 against the underside of which a coil compression spring 61 reacts. It will be observed that the coil compression spring 61 surrounds the insulating sleeve 38 and that its lower end bears against the flanged metallic fitting 56. The spring 61 is employed for effecting rapid movement of the rodlike contact 41 from the closed to the open position in a manner to be described.

With a view to maintaining contact engagement between the rodlike contact 41 and the metallic sleeve 59 as the latter moves downwardly with respect to the insulating sleeve 38 while the former is held stationary by the resilient fingers 53, resilient contact fingers 62 are secured to the underside of the flanged metallic fitting 56 and bear outwardly against the inner surface of the sleeve 59. At the lower end of the metallic sleeve 59 there is a closure disc 63 which is provided with apertures 64 for venting the interior of the auxiliary circuit interrupter 25. The closure disc 63 also has a central aperture 65 through which the indicator 55 projects and from which it may be withdrawn as shown in Figure 8.

It is desirable to limit the relative movement apart of the metallic sleeve 59 and the insulating sleeve 38 and to prevent accidental reclosure of the contact 39 and 41. For this purpose the latteris provided with an annular slot 66 and the former carries a detent 67 spring biased by a resilient arm 68 that is secured by a rivet 69 to the outer surface of the sleeve 59 near its-upper end. The inner end of the detent 67 rides over the surface of the insulating sleeve 38 until it reaches the annular slot 66. As shown in Figure 8, the detent 68 has moved through an opening '70 in the .end ring 60 and into the annular slot 66 prior to the forcing of the shoulder 52 past the resilient fingers Y53 and separation of the 'rodlike contact 41 from the ringlike contact 39 where it prevents any further downward movement of the metallic sleeve 59 with respect to the insulating sleeve 38. Should the downwardly acting force applied to the sleeve 59 be released, the detent 67 reposing in the annular slot 66, prevents the spring 61 from effecting accidental reclosure of the contacts 39 and 41.

Intermediate the ends of the metallic sleeve 59 a metallic support bracket 73 is clamped. Formed integrally therewith, Figure 6, is an arm 74 which is arranged to receive a detachable fitting 75 mounted on the upper end of a live line stick 76'. Ordinarily the live line stick 76 is a suitably seasoned and treated wood pole which has high insulating qualities and is arranged to be manipulated by a lineman on the ground for operating various live line tools which are employed for performing operations on a circuit while the conductors are energized at high voltage. The fitting 75 is clamped to the arm 74 by a bolt 77 and a cooperating wing nut 78.

Since the fuse tube 15 swings in an are about the pivot 14 and the pull ring 22' moves therewith, provision is made for accommodating this relative movement of the pull ring 22 with respect to the auxiliary circuit interrupter 25. In accordance with this invention, there is provided a contact arm, shown generally at 79, which is rockably mounted on the arm 74. For this purpose a shaft 80 is employed and it has formed integrally therewith a shoulder 81, Figure 7, which cooperates with a stop pin 82. The shoulder 81 and stop pin 32 limit the movement of the contact arm 79 in a clockwise direction but permit it to swing in a counterclockwise direction to the position shown by the broken lines in Figure 7. A torsion spring -33, having one end 84 fastened to the arm 74 and the other end 35 fastened to a flange 86 secured by a transverse pin 87 to the outer end of the shaft 80, serves to bias the contact arm 79 against the stop pin 82. If desired, the shoulder 81 and stop pin 82 may be omitted and the spring 83 can be arranged to function as a centering spring biasing the contact arm 79 to the position shown by the full lines in Figure 7 and permitting it to swing therefrom in either direction as may be required in the manipulation of the auxiliary circuit interrupter 25.

Referring particularly to Figure 6, it will be observed that the contact arm 79 includes a shank 90 which is fixed on. and carried by a head 91 which forms an integral part of the shaft 80. At its upper end the shank 90 has a contact finger 92 extending at right angles with a bulbous outer end 93 to facilitate entry into the opening in the pull ring 22. With a view to maintaining electrical con tact with the pull ring 22 a cooperating contact finger 94 is employed. It extends parallel to the contact finger 92 and has an inclined outer end 95 to facilitate cooperation with the pull ring 22. The contact finger 9 1- extends at right angles from and is carried by a sleeve 96 which is telescoped over the shank 90 and which is biased upwardly by a coil compression spring 97. Moverment of the sleeve 96 with respect to the shank 90 is limited by a slot 98 in the sleeve 96 and a stop pin 99 extending therethrough from the shank 90.

It will be understood that the spring 33 transmits its force through the contact finger 92 to bear against the inside of the pull ring 22. Where this contact engagement is sufficient, particularly where the spring functions as a centering spring as described above, suflicient contact pressure is maintained against the pull ring 22 so that, if desired, the cooperating contact finger 94 and parts associated therewith can be omitted. In such case reliance is placed on the biasing action of the spring 83 for maintaining the desired contact engagement.

In Figure 10 of the drawings, there is illustrated a modified contact arm construction. As shown generally at 102, the contact arm is constructed so that the contact fingers thereof bear radially outwardly against the opening of the pull ring 22. For this purpose there is provided a sleeve 103 which is carried by the head 91 on the outer end of the shaft 80. Projecting at right angles from the sleeve 103 is a contact finger 104 whose outer end 105 is inclined upwardly to facilitate entry into the pull ring 22. Slidably mounted within the sleeve 103 is a shank 106 having a transverse pin 107 extending therefrom through a slot 108 in the sleeve 103 to limit relative movement between the shank 106 and the sleeve 103. The shank 106 carries a contact finger 109 at its upper end which extends parallel to the contact finger 104 and has an inclined outer end 110 to facilitate entry into the opening of the pull ring 22. The contact finger 109 also has a shoulder 111 which cooperates with the pull ring 22 to maintain mechanical and electrical engagement therewith. A coil compression spring 112 reacts between the upper end of the sleeve 103 and a washer 113 secured to the upper end of the shank 106 for biasing the contact finger 109 upwardly so as to maintain good mechanical and electrical contact engagement with the inner surface of the pull ring 22 at diametrically opposite locations.

In operation the auxiliary circuit interrupter, carried by the live line stick 76 as illustrated in Figure 3, is manipulated so that the eye member 29 engages the conducting arm 24 on the sleet hood 23 and the contact arm 79 engages the pull ring 22. This is facilitated by the swivel mounting of the eye member 29 and the fact that the metallic sleeve 59, to which the live line stick '76 is attached by the support bracket 73, is rotatable with respect to the longitudinal axis of the auxiliary circuit interrupter, more particularly the longitudinal axis of the insulating sleeve 38. It will be understood that either form of contact arm 79 or 102 can be employed. When the auxiliary circuit interrupter 25 is positioned as described, the contacts 39 and 41 therein are in engagement and the parts 7 are positioned as shown more clearly in Figure 7. A shunt circuit then is established between the upper terminal assembly 12 of the circuit breaker It) and the fuse tube terminal assembly 16 through the conducting arm 24, eye member 29, relatively fixed conducting member 26, conducting sleeve 4 0, contacts 3? and 41, flanged metallic fitting 56, resilient contact fingers 62, metallic sleeve 59, support bracket 73, and contact arm 79 to the pull ring 22.

Now the live line stick 76 is manipulated by pulling on it lengthwise to the position shown in Figure 4. Since the support bracket 73 is fastened to the metallic sleeve 59 and since the eye member 29 prevents movement of the insulating sleeve 38, the metallic sleeve 59 is moved away from the insulating sleeve 38, as shown in Figure 4, and compression of the coil spring 62 is begun. However, the resilient fingers 53 are strong enough to hold the rodlike contact 41 against the force initially exerted by the spring 61 and thus, while the metallic sleeve 59 is being moved downwardly to the position shown in Figure 4, the contacts 3% and lit remain in engagement completing the shunt circuit previously described. Since the contact arm 79, which is in engagement with the pull ring 22, moves downwardly with the metallic sleeve 59, as manipulated by the live line stick 76, the arm 20 is operated so as to lift the sleeve 17 and remove the hook 218 from engagement with the roller 19. This is followed by a swinging movement of the fuse tube to the position shown in Figure 4. Because the shunt circuit is maintained by engagement of the contacts 39 and 41 within the auxiliary circuit interrupter 25, no arcing occurs between the terminal assemblies 12 and 16 when they separate.

As illustrated in Figure 5, the continued manipulation of the live line stick 76 causes the fuse tube 15 to swing further away from the closed position. This is accompanied by a further compression of the spring 61. The metallic tube 59 is operated to the position shown in Figure 8 where the detent 67 enters the groove 66 and prevents further movement apart or reverse movement. After this occurs and the spring 61 has been compressed to a point where the force exerted by it is greater than the restraining force exerted by the resilient fingers 53 on the shoulder 52, they are no longer capable of restraining downward movement of the rodlike contact 41. Alternatively the coil compression spring may be compressed to the solid position where the downward pull on the live line stick 76 is transmitted directly to the flanged metallic fitting 56. In either event, after the metallic sleeve 59 has been locked by the detent 67 against reverse movement, the rodlike contact 41 is moved downwardly to the position shown in Figure 8 of the drawings where its upper end is out of engagement with the ringlike contact 39. An are is drawn therebetween and it plays on the bore of the liner 43 of arc extinguishing material. The spring 61 now biases the rodlike contact 41 downwardly through the metallic sleeve 59 to increase the distance between the upper end of the former and the ringlike contact 39. This effects a corresponding extension of the arc. The trailer following the movement of the rodlike con tact 41 into the bore in the liner 4-3 assists in extinguishing the arc in a manner readily understood. At this time the external isolating air gap between the terminal assemblies 12 and 16 and the break distance over the insulating sleeve 38 are equal to or greater than the break distance between the contacts 39 and 41 within the auxiliary circuit interrupter 25, thereby avoiding the likelihood of external flashover due to high recovery voltage incident to the circuit interruption. While the rodlike contact 41 is moving downwardly through the metallic sleeve 59, contact engagement therebetween is maintained through the resilient contact fingers 62.

It will be observed that the indicator 55, as shown in Figure 8 of the drawings, is totally enclosed by the metallic sleeve Sh at the time that the contacts 39 and 41 are first separated. Further it will be observed that the indicator 55 projects from the bottom of the metallic sleeve 59 when the contacts 39 and 41 are in engagement as shown in Figure 7. Also it will be noted that, when the contacts 39 and 41 are in the fully opened position, the indicator again projects from the lower end of the metallic sleeve 59. This provides a positive indication to the lineman of the position of the contacts 39 and 41, so that he has a definite knowledge that they are either in the fully closed or fully open position.

The lineman now manipulates the auxiliary circuit interrupter 25 in such manner as to disengage the eye member 29 from the conducting member 26. This is facilitated by the fact that the metallic sleeve 59 is rotatable about the longitudinal axis of the device. Thereafter he further manipulates the auxiliary circuit interrupter 25 to disengage the contact arm 79 from the pull ring 22. This allows the fuse tube 15 to swing to the full open position under the influence of gravity.

For further use, the auxiliary circuit interrupter 25 is restored to the closed position, shown in Figure 7, by withdrawing the detent 67 from the slot 66 and allowing the metallic sleeve 59 to be moved by the spring 61 back over the insulating sleeve 38, thereby operating the rodlike contact 41 back into contact engagement with the ringlike contact 39. Of course, this is accomplished only when the device is removed entirely from proximity to an energized part of the electric power system.

Since certain further changes can be made in the foregoing construction and different embodiments of the invention can be made without departing from the spirit and scope thereof, it is intended that all matter shown in the accompanying drawings and described hereinbefore shall be interpreted as illustrative and not in a limiting sense.

What is claimed as new is:

1. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having separable energized stationary and relatively movable conducting parts normally carrying line current, said movable conducting part being movable along a path in a plane including said stationary part away from the latter to interrupt the line current, pull ring means on said movable part for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means carried at one end by said stationary conducting part and extending generally normal to the plane of movement of said movable part for detachably receiving over its other end another terminal of the auxiliary circuit interrupter.

2. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at one end to said other terminal assembly and extending generally normal to the plane of swinging movement of said conducting member including said part of said other terminal assembly for detachably receiving over its other end another terminal of the auxiliary circuit interrupter.

3. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at one end to said other terminal assembly and extending generally parallel to the pivot axis of said conducting member for detachably receiving over its other end another terminal of the auxiliary circuit interrupter.

4. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at its inner end to said other terminal assembly and extending generally normal to the plane of swinging movement of said conducting member including said part of said other terminal assembly for detachably receiving over its outer end another terminal of the auxiliary circuit interrupter, said conducting and anchor means at its outer end having a portion extending away from the direction of opening movement of said conducting member to reduce the likelihood of said other terminal of said auxiliary circuit interrupter slipping ofi of the same.

5. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at its inner end to said other terminal assembly and extending generally parallel to the pivot axis of said conducting member for detachably receiving over its outer end another terminal of the auxiliary circuit interrupter, said conducting and anchor means at its outer end having a portion extending away from the direction of opening movement of said conducting member to reduce the likelihood of said other terminal of said auxiliary circuit interrupter slipping 0115 of the same.

6. In combination, a circuit isolating device, such as a. disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly to swing in a plane including said terminal assemblies and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at one end to said other terminal assembly and extending generally normal to said plane of swinging movement of said conducting member for detachably receiving over its other end another terminal of the auxiliary circuit interrupter, the plane containing the pivot of said conducting member and said conducting arm being located on the side of the plane containing said pivot and said pull ring means away from the direction of opening movement of said elongated conducting memher.

7. In combination, a circuit isolating device, such as a disconnecting fuse, disconnecting switch or the like, having terminal assemblies in insulated spaced relation and an elongated conducting member pivoted at one end to one terminal assembly to swing in a plane including said terminal assemblies and carrying at the other end contact means engageable with a part of the other terminal assembly for completing the circuit between said terminal assemblies and permitting opening of the same by separation thereof, pull ring means on said conducting member for detachably receiving one terminal of an auxiliary circuit interrupter, and conducting and anchor means secured at one end to said other terminal assembly and extending generally parallel to the pivot axis of said conducting member for detachably receiving over its other end another terminal of the auxiliary circuit interrupter, a line interconnecting said pivot axis and said conducting member being located on the side of a line interconnecting said pivot axis and said pull ring means away from the direction of opening movement of said elongated conducting member.

References Cited in the file of this patent UNITED STATES PATENTS 2,263,513 Meyer Nov. 18, 1941 2,310,466 Schultz Feb. 9, 1943 2,521,155 Earle et a1. Sept. 5, 1950 2,629,794 Hubbard et a1 Feb. 24, 1953 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 2,816,983 December 1'7, 195'? Sigurd I, Lindell It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 10, line 10, after "means" insert including a conducting arm line 37, for "member" read and anchor means Signed and sealed this 10th day of iiarch 1959 (SEAL) Attest:

KARL H. AXLINE ROBERT C. WATSON Attesting Oificer Commissioner of Patents UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nos 2,816,983

December 17, 1957 Sigurd In Lindell It is herebj certified that error appears in the -printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 10, line 10, after "means" insert including a conducting arm line 3'7, for "member" read and anchor means Signed and sealed this 10th day of March 195% (SEAL) Attest:

KARL H, AXLINE ROBERT C. WATSON Attesting Officer Commissioner of Patents 

